Hanoi (VNA) - Hanoi’siconic Hoan Kiem Lake has been severely polluted through the years and must becleaned to save the threatened living creatures there, experts said.

Hoang Thi Thu Huong, Deputy Director of the Institute forEnvironmental Science and Technology under the Hanoi University of Technology,said the lake was contaminated and had lost the ability to clean itself.

The thick mud at the bottom of the lake contains heavy metals andtoxic gases, affecting the habitats of creatures, she was quoted as saying byKinh te va do thi (Economic and Urban affairs) newspaper.

The high density of algae means there is not enough oxygen anddredging work is a must to protect the lake’s ecosystem and restore its beauty,she said at a public consultation on the environmental impact assessment reportconducted by her institute, co-organised by the Hanoi Sewage and Drainage Ltd andthe People’s Committee of Hoan Kiem district.

While most scientists and residents living in the areas around thecapital’s central pivot agreed on the need to improve the lake’s water quality,scientists said the environmental improvement plans for the lake should beconducted prudently to redress its pollution while protecting its ecosystem andbiodiversity.

Duong Duc Tien, a biological expert, said the process ofrehabilitation and dredging must be carefully considered to make sure it doesnot badly affect the lake’s habitats. The types of fish and algae living in thelake mist be catalogued in detail, he added.

Mai Dinh Yen, another expert, agreed, saying mud layers should bemaintained during the dredging process since it is the habitat for manyspecies.

Nguyen Ngoc Ly, director of the Centre for Environment and CommunityResearch, proposed that Hoan Kiem district set forth regulations to preventresidents from releasing fish into the lake. "Hoan Kiem Lake has manykinds of alien species. Some people even bring sacks of eel and snails to thelake," she said.

Trinh Dang Khoa, who resides on Dinh Tien Hoang Street, said thatdespite efforts in recent years to improve the lake’s water quality, theresults did not meet residents’ expectations.

Nguyen Thi Minh Ha, chairwoman of the Ly Thai To Fatherland Front,stressed the need to raise the awareness of local residents to the lake’secosystem protection.

Phan Hoai Minh, Deputy General Director of Hanoi Sewage and DrainageLtd, the cleanup project’s investor, said the company will instruct theconsultants to review all suggestions, particularly those on biodiversity inthe environmental impact assessment. Once completed, the report will besubmitted to the scientific council at ministerial and municipal level forapproval.

Covering about 12 ha, Hoan Kiem Lake (also known as Returned SwordLake) is located in the centre of the capital. Apart from its spiritual andcultural values, it is considered a scenic venue, a hub for weekend relaxationfrom the chaos and bustle of the city.-VNA